The present invention generally relates to a soft, readily expandable vacuum bell assembly and, specifically, to a soft, readily expandable vacuum bell assembly for obstetrical use in the delivery room in an effective and efficient manner.
In some instances during the birth of a child a completely natural birthing process is not possible. Therefore, assistance must be rendered by the attending physician in order for the child to be delivered from the birth canal. In the past, forceps and other like devices which tend to be bulky and hard to handle were employed to provide assistant during the course of delivery. These devices often caused injury to the mother and child. Vacuum extractors have also been employed in vacuum extraction assemblies. In 1953 the Malmstrom metal cup was introduced.
In 1965, a vacuum extraction cup made of polyethylene was first marketed. These vacuum bells or cups are of the type hereafter described in U.S. Pat. No. 3,202,152 which are used during infant delivery to provide assistance in maneuvering the baby's head in the birth canal. In this way, a proper presentation of the baby is made to the obstetrician thereby facilitating the birthing process. The vacuum bell, which is operated by applying subatmospheric pressure, is secured to the head of a child and then manipulated properly to augment the parturient forces exerted by the mother during the delivery process and withdraw the child from the birth canal. By using the vacuum forces exerted by the bell assembly, the amount of effort needed to be expended by the mother is reduced, the expulsion of the baby from the birth canal can be more easily facilitated, and the time the baby needs to spend in the delivery process is greatly reduced.
In U.S. Pat. No. 3,202,152, a vacuum-assisted device for attaching to the head of a child is provided which includes an elongated hollow stem is joined to a vacuum cup, and is used to manipulate the cup during delivery. The device is made of a stiff polymeric material which is easily cleaned and sterilized in the event that such should be reused. The stiff vacuum bell assembly employs a wide range of pulling forces, in the form of a subatmospheric vacuum, accompanied with proper positioning, to be employed in the manipulation of the device. Many obstetricians, however, do not like to use this device because they perceive that the use of a vacuum-assisted device fabricated of a stiff polymeric material is a safety problem which substantially increases the chance of injury to the infant during delivery.
To avoid traumatizing the baby's scalp during the delivery process, great care must be taken to balance the need to maintain contact with the baby's head while avoiding pulling the scalp into the vacuum bell by the use of excessive vacuum. Thus, some cranial cups include a deflector shield or plate, placed across the bottom of the bell and over the exhaust hole, so that as the bell is drawn down onto the baby's head by the external air pressure, the scalp will come to rest against the plate, providing an extended area over which to distribute the pressure. Further, existing vacuum bells usually use an exhaust tube extending axially from the bell itself to a source of vacuum. The exhaust tube can include a handle for controlling the use of the vacuum bell during the birthing process. For example, the natural tendency during use of a vacuum bell such as described in U.S. Pat. No. 3,202,152 is to bend the handle to obtain a better grip thereon. This will often lift one side of the cranial cup from the baby's scalp. This breaks the vacuum seal, requiring the cup to be reseated, and the vacuum redrawn, taking precious time from the limited amount permitted to avoid traumatizing the baby.
Accordingly, another prior art vacuum-operated device has been developed which overcomes some of the problems described above regarding the use of vacuum bell assemblies fabricated of stiff polymeric. In U.S. Pat. No. 3,765,408, a soft obstetric vacuum cup and stem assembly is used for assisting child delivery. The obstetric cup which comprises a cup-shaped body made of an elastic material, a plurality of recessed portions formed around the upper inner periphery of the cup-shaped body in a spaced apart relationship, a suction tube communicating with the bottom of the cup-shaped body and extending outwardly therefrom, and a plurality of passages formed through the wall of the cup-shaped body to communicate the recessed portions with the suction tube. The cup is configured with a hemispherically-shaped outer and inner wall portion, the inner wall portion being inwardly curved at its outer edge.
Therefore, a need exists for a soft, readily expandable vacuum bell assembly for obstetrical use in the delivery room in an effective and efficient manner, which provides a high degree of safety to a baby during the birthing process, but at the same time exhibits a sufficient amount of attachment to the head of the infant which augments the parturient forces exerted by the mother so that the delivery process can be affected.